Targeted Immunotherapy May Prevent Toxicity in Bladder Cancer

Administering immunotherapy near the tumor site prevents adverse events associated with the current administration method.

Findings from a recent study suggest that targeted immunotherapy may present a promising method for treating bladder cancer.

New antibody-based immunotherapy treatments have become very popular for treating cancer, and have been successful in many cases. Unfortunately, like most cancer treatments, new immunotherapy options can also cause adverse effects.

In a study, published by the European Journal of Immunology, investigators discovered that an alternative method of administering the immunotherapy resulted in the same cancer outcomes without harming other healthy cells and tissues. These findings could potentially lead to more targeted treatments and improved patient outcomes.

Immunotherapies are used to increase the body’s immune response to attack and kill cancer cells, and can be used to treat metastatic cancers, such as melanoma and bladder cancer. Compared with chemotherapy and other treatments, immunotherapy itself does not kill the cancer cells, but rather enlists the help of the immune system.

These treatments are typically injected into the blood, which exposes the entire body to the treatment, and increases the likelihood of adverse events occurring throughout the body. Certain reports indicate that gastrointestinal, hepatic, and endocrine adverse events may be experienced by patients.

Instead of the traditional method, researchers in the current study discovered that an alternative method, allowing for the administration of the drug inside or close to the tumor, would prevent adverse health events, while eliciting the sought response from the immune system. These findings were discovered among mice models of bladder cancer.

The investigators found that local immune activation at the tumor site had the same effect on the tumor, as was seen with the current method of drug delivery, according to the study.

“We found that the therapy that we tested in a model system of bladder cancer could stimulate the immune cells to find and attack the cancer cells, even if it was administered locally,” said lead author Sara Mangsbo, PhD. “These results are very promising since they indicate that it's not necessary to activate the body's whole immune system, but only the one that is relevant in the tumor. This way adverse events caused by the drug can be reduced.”

Specifically, investigators saw these results when administering the antibodies close to the tumor. According to the study, these findings reinforce previous findings where the investigators discovered that a direct immune stimulatory antibody was more effective locally at the tumor compared with administration through the blood.

The hope with these immunotherapy treatments is that the immune cells can seek out the potential metastases and prevent them from ever becoming a tumor. Additional research is needed to understand if this is occurring and the underlying mechanisms behind this, the study concluded.